ci: use travis instead of appveyor (#4168)

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## Types of changes
<!--- What types of changes does your code introduce? Put an `x` in all the boxes that apply: -->
- [ ] Bug fix (a non-breaking change which fixes an issue)
- [ ] New feature (a non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing functionality to change)


## Description
<!--- Describe your changes in detail -->
<!--- Why is this change required? What problem does it solve? -->
<!--- If it resolves an open issue, please link to the issue here. For example "Resolves: #1337" -->


## Checklist:
<!--- Put an `x` in all the boxes that apply. -->
<!--- If your change requires a documentation PR, please link it appropriately -->
<!--- If you're unsure about any of these, don't hesitate to ask. We're here to help! -->
- [ ] My change requires a change to the documentation.
- [ ] I have updated the documentation accordingly. (PR: #)
- [ ] I have added tests to cover my changes (if not applicable, please state why)
- [ ] All new and existing tests are passing.

.travis.yml

@@ -0,0 +1,16 @@
+os: windows
+language: node_js
+node_js:
+  - "node"
+cache:
+  yarn: true
+  directories:
+    - node_modules
+install:
+  - yarn install
+  - yarn lerna link
+  - yarn build
+script:
+  - node --version
+  - yarn --version
+  - yarn test

appveyor.yml

@@ -1,38 +0,0 @@
-# Test against the latest version of this Node.js version
-environment:
-  nodejs_version: "Current"
-
-cache:
-  - 'node_modules -> yarn.lock'
-  - '%LOCALAPPDATA%\\Yarn -> yarn.lock'
-
-image: Visual Studio 2017
-
-shallow_clone: true
-
-# Install scripts. (runs after repo cloning)
-install:
-  # Get the latest stable version of Node.js or io.js
-  - ps: Install-Product node $env:nodejs_version
-  # Install modules
-  - yarn install
-  # Link dependencies
-  - yarn lerna link
-  # Build packages
-  - yarn build
-
-# Post-install test scripts.
-test_script:
-  # Output useful info for debugging.
-  - node --version
-  # - npm --version
-  - yarn --version
-  # run tests
-  - yarn test:fixtures -w=2
-  - yarn test:unit -w=2
-
-# Don't actually build.
-build: off
-
-# Do not build feature branch with open Pull Requests
-skip_branch_with_pr: true

test/fixtures/cli/cli.build.test.js

@@ -6,7 +6,7 @@ const execify = promisify(exec)
 const rootDir = __dirname
 const nuxtBin = resolve(__dirname, '../../../packages/cli/bin/nuxt.js')
 
-describe.skip.appveyor('cli build', () => {
+describe('cli build', () => {
   test('nuxt build', async () => {
     const { stdout } = await execify(`node ${nuxtBin} build ${rootDir} -c cli.build.config.js`)
 

test/fixtures/cli/cli.gen.test.js

@@ -6,7 +6,7 @@ const execify = promisify(exec)
 const rootDir = __dirname
 const nuxtBin = resolve(__dirname, '../../../packages/cli/bin/nuxt.js')
 
-describe.skip.appveyor('cli generate', () => {
+describe('cli generate', () => {
   test('nuxt generate', async () => {
     const { stdout } = await execify(`node -r esm ${nuxtBin} generate ${rootDir} -c cli.gen.config.js`)
 

test/unit/cli.test.js

@@ -20,7 +20,7 @@ const close = async (nuxtInt) => {
   }
 }
 
-describe.skip.appveyor('cli', () => {
+describe('cli', () => {
   test('nuxt dev', async () => {
     let stdout = ''
     const env = process.env

test/utils/setup.js

@@ -1,7 +1,3 @@
-const isAppveyor = !!process.env.APPVEYOR
-describe.skip.appveyor = isAppveyor ? describe.skip : describe
-test.skip.appveyor = isAppveyor ? test.skip : test
-
 const isWin = process.platform === 'win32'
 describe.skip.win = isWin ? describe.skip : describe
 test.skip.win = isWin ? test.skip : test